Measurements Definition and 397 Threads

Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. The scope and application of measurement are dependent on the context and discipline. In natural sciences and engineering, measurements do not apply to nominal properties of objects or events, which is consistent with the guidelines of the International vocabulary of metrology published by the International Bureau of Weights and Measures. However, in other fields such as statistics as well as the social and behavioural sciences, measurements can have multiple levels, which would include nominal, ordinal, interval and ratio scales.Measurement is a cornerstone of trade, science, technology and quantitative research in many disciplines. Historically, many measurement systems existed for the varied fields of human existence to facilitate comparisons in these fields. Often these were achieved by local agreements between trading partners or collaborators. Since the 18th century, developments progressed towards unifying, widely accepted standards that resulted in the modern International System of Units (SI). This system reduces all physical measurements to a mathematical combination of seven base units. The science of measurement is pursued in the field of metrology.

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  1. D

    Light, Vacuum, Speed, and Measurements

    They say often that light only travels at light speed in a vacuum. That it slows down in air and water. I do not think this is true - correct me if I am wrong as I usualy am :shy: All atoms are vacuum. Light is energy that is not made of atoms, or in other words it is smaller then atoms if...
  2. S

    Charge carrier concentration measurements in working electrode

    Dear All I will be grateful for any idea on how to measure electrochemically the charge carrier in an electrode say working electrode made of Al. Thank you from advance Shay
  3. N

    Is Strong Nuclear Force Measured Using F=p*E/hbar Equation?

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  4. 7

    Can Magnetic Field Strength Decrease with Distance in Plasmas?

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  5. G

    Discover the Truth About Weak Measurements in 2007 | Postbiota Discussion Thread

    http://postbiota.org/pipermail/tt/2007-May/000515.html Does anyone know what happened with these experiments?
  6. O

    Local measurements on an entangled pair. (My understanding)

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  7. T

    Engineering 101: Understanding One Meter (1 m) & Weight Measurements

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  8. M

    Advantages of Radian Measurements

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  9. H

    Fluoride Ion selective electrode measurements

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  10. R

    G from cosmological measurements

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  11. Loren Booda

    Is the physical whole a sum of quantum measurements?

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  12. C

    Can operators describe a single or many measurements simultaneously?

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  13. R

    Measuring Time Intervals: How Precise Can We Go?

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  14. T

    Why Does the Measurement Problem Terrify Physicists?

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  15. M

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  16. Simfish

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  17. G

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  18. H

    Measurements on YBCO, and their meaning.

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  19. H

    A hyperbolicshape of the universe, despite measurements

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  20. L

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  21. O

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  22. T

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  23. J

    Question about Measurements and sig. figs.

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  24. E

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  25. S

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  26. L

    Is the QM axiom for measurements misleading?

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  27. E

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  28. S

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  29. B

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  30. D

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  31. O

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  32. A

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  33. S

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  34. S

    Calculate a spring constant using measurements from a Hooke's Law

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  35. bayan

    Analysis of Experimental Errors on Wavelength and Angle Measurements

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  36. P

    Correction to temperature measurements

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  37. A

    Calculating Filling Time for a Large Bottle of Water

    Hi, I just started my school year, and we're currently on Measurements. I need help with this one problem that my teacher assigned. The biggest bottle ever made was 193 gallons (730,505cc). If the bottle were filled with water of a density of 1000 kg/m^3 at the leisurely rate of 1.8 g/min...
  38. J

    Measurements of time/distance be dependent on an object's velocity

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  39. F

    Lasers in Measurements: Learn How to Use Them

    Hi! I have to make a presentation about the usage of lasers in measurements, but I am not sure what I should include. I thought of something like using laser beams for measuring distances, but I don't know how exactly this can be done and what else can be measured with lasers. I'd be greatful if...
  40. Z

    Is there a site to do conversions of measurements

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  41. C

    Problem involving relative measurements

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  42. C

    Fluid Mechanics - Pressure measurements

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  43. B

    I need clarification about Bell state Measurements

    The four bell states are 1: (|00>+|11>)(2)^-0.5 2: (|00>-|11>)(2)^-0.5 3: (|01>+|10>)(2)^-0.5 4: (|01>-|10>)(2)^-0.5 I'm looking at super dense coding and the way i thought of it at first was that if a measurement of the first qubit was made then if we consider the first bell state (1)...
  44. M

    Solving Vector Addition Without Angle Measurements

    In class today we had a brief lesson on vector addition. I understand how to calculate the resultant when given a magnitude and angle measurent for each vector, but my teacher gave me no other examples. I have tons of homework problems that do not give me this information, but I am expected to...
  45. N

    Area Measurements: Converting Feet to Sq. Feet for Horse Stall

    I need help converting feet to area or square feet for my horse stall. I have two stalls, each of which is 12' x 12'. I want to put a thickness of 2.25" of lime over the barn floor surface of these stalls. How many 50 lb bags would I need to buy? Can you show me the equation also? Thank...
  46. T

    Half life measurements on foams

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  47. A

    What is the correct method for combining systematic errors in measurements?

    Say you have two measurements of the same quantity: t = 500 +- 20 +- 3 t = 600 +- 90 +- 10 where the first error is statistical and the second is systematic. What is the correct way of combining the systematic errors? i.e., if I want to put both measurements together into t = x +-...
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